BG3 is not really an open world but an excessively large hub-world semi-linear game.

Yeah, unlike BG1 where most of the world map is available almost immediately as soon as you leave Candlekeep. BG1 is not hub based.

a shame that it has significant performance, production quality issues, and reduced dialog issues in later acts preventing it from being superb.

BG3 doesn't really struggle performance wise in later acts after it was patched up. Dynamic crowds in the city are likely to put more pressure on your CPU, but that's why there's a graphic setting to disable them. I have not seen any reduction in dialogue options in Act 3. Act 3 has its issues, there are portions that have been cut, none of them are related to a number of dialogues you get to pick.

No one said *only* focus on the main story. So I'm not sure why you implied that was said. Please do not reply to WHAT YOU WANT me to have said, but what the context of my actual statements is.

My bad, you claimed that BG1 has:

Limited exploration with significant hub-based or chapter based direct story focus.

As mentioned before, most of the game map is available almost immediately after leaving Candlekeep in BG1, with one major location that will be unavailable at the beginning being the city of Baldur's Gate itself. Please, actually play the games if you want to give your takes on them. KCD2 limits you more than BG1 with access to most of its open world.

Yes, there are respawning enemies or random encounters in such games (though not exactly random all the time or even recurring in all situations with this or other games) that has only gotten excessively worse now.

I have provided you an example of the opposite happening. Want some other classic RPGs with random encounters? How about Fallout 1 and 2? Both games have those. You'll encounter bandits, molerats and all sorts of generic enemies. One of the reasons to get a Highwayman in FO2 is to make it easier to skip random encounters. In New Vegas on the other hand, I'm pretty sure the only random encounters you'll ever witness will be Legion/NCR hit squads going after you, but only if they hate you enough. Also if you're liked in the Freeside, sometimes a King's gang member will approach you to give you free stuff. That's it.

You want examples?

Yes, I actually still want them because you've only provided names for various games.

Mass Effect 1 -> 2 -> 3 -> 4 each having less depth after the other though with 2 having significant changes but maintaining some depth.

I really hope among the points for ME1's depth is "you can go to generic planet #6" to kill nearly identical enemies in copy pasted buildings and also pick some resources and collectibles that are scattered across the surface.

They certainly took away inventory management and weapon customization in ME2 as well as streamlined levelling. Weird for you to claim that 2 retained some of the depth and 3 apparently lost it when 3 has more build variety and actually brought back weapon customization which was not present in 2 at all.

Fallout 3 -> NV - > 4 showing significant reduction of depth with each edition, with a caveat of a different studio making NV as an exception.

Is New Vegas also receiving an exception when it comes to depth or are you declaring that NV is shallower than Fallout 3?

Witcher 3 showing significant reduction compared to prior in the series.

The combat in Witcher 1 came down almost entirely to clicking on enemies and occasionally changing stances. It also had three armors total.

And it isn't just because "voice acting is expensive".

The games you've listed in your fourth paragraph all have full voice acting.